They recorded an unusual formation. The forest phenomenon is astonishing

The video quickly spread across the web, and the comments were full of speculation – from guesses about an unknown species of animal to suggestions that it was a sign of impending disaster.

What is mold?

Although it looks disturbing and almost alien, mold is a natural phenomenon. It consists of thousands of fly larvae, most often fungus gnats. These small insects, resembling fruit flies, can form tight, synchronized groups in the larval stage, moving in a way that resembles the migration of a single organism.

Why do they do this? This is not fully known, as emphasized by foresters from Świerklaniec: "It is not fully known why the larvae of the species Fungus gnat create such crawling structures and what is the purpose of their migration."

Such aggregations can reach a length of several meters, and the crawling larvae secrete mucus that facilitates movement over uneven terrain and probably helps maintain a compact structure. Scientists speculate that the larvae's migration may be related to the search for more favorable conditions for further development or protection from predators - a mass crawling in a group looks like a much larger organism, which may deter threats.

A rare and difficult to observe phenomenon

The mold occurs rarely and is very difficult to observe. It is known primarily from mountainous areas - the Tatras, Bieszczady , and also from some areas of the Żywiec Beskids and the Białowieża Forest. It usually appears in damp, shaded forests, most often in the summer, when conditions are optimal for larvae activity.

Although the first mentions of such a phenomenon appeared in the 17th century – at that time in Silesia, zoologist Caspar Schwenckfeld described them as "Ascarides militares" – to this day scientists are unable to clearly determine what drives the larvae to this collective march. In Poland, only a few dozen cases of observations of the mold have been recorded so far.

Folk beliefs and symbolic meaning

For centuries, the mold has stirred emotions and has been the subject of numerous legends. In folk tradition, its appearance had a special meaning. Depending on the region and beliefs, it was treated as an omen – good or bad. As the Świerklaniec Forest District noted: "According to folk beliefs, the appearance of the mold was treated in two ways: some considered it a prophecy of approaching misfortunes, others believed it was a harbinger of happiness, success and good harvests."

In some regions of Poland, such as Podhale, mold was considered a sign of good harvest – it was collected, dried and stored in barns as an amulet for good luck. It was believed that if the larvae crawled in a certain direction – for example, north – it meant good times were coming.

Fascination and disgust – people's reactions

The film published by the Świerklaniec Forest District stirred mixed emotions. Some were fascinated by the unusual movement and behavior of the larvae, while others wrote that the recording made them gag. This is a typical reaction to contact with something that looks unnatural, although it is completely consistent with biology.

Tourists and internet users have reacted in a similar way in the past – for example, during a recording of a larva in the Bieszczady Mountains a few years ago, where many witnesses initially thought they were dealing with a snake or a mysterious creature from legend. Even experts admit that the sight of such a large number of larvae moving as one body can arouse consternation and sometimes even fear.

Read also: These species are not afraid of winter, they will easily endure the freezing cold Read also: Mold in the Beskids. A recording of a mysterious crawling mass is an internet hit